Baluster structure of handrail

ABSTRACT

A baluster structure of handrail includes a steel-bar threaded central post, which is circumferentially enclosed by a plastic jacket and a plastic decorative portion. The steel-bar threaded central post has top and bottom respectively forming first and second joint sections. The second joint section is mounted to a stairway and the first joint section is mounted to an underside of the handrail to form a baluster. The threads of the upper and lower sections and the thread-free middle section of the steel-bar threaded central post are enclosed by the integrally formed plastic jacket and plastic decorative portion, whereby the plastic jacket and the plastic decorative portion are rotatably fixed. The baluster is mounted to the stairway to support a handrail. The baluster is of greater strength, does not deform and bend, is safe and corrosion resistant, has an extended life span, and is environmentally conservative.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the technical field of baluster ofhandrail, and in particular to a socket structure that is thermallyfusible through application of ultrasonic wave for easy realization ofmachine-based automatic assembling.

2. The Related Arts

Conventional handrails comprise balusters that are generally made ofwood. The growth of woods takes time and the consumption of woodmaterial for furniture and buildings of human society is great, farexceeding the natural supply of wood. This generally leads to a rapidincrease of cost of wood due to lacking of supply. Further, poor qualitytimbers might be used, such as woods of reforestation that has not fullygrown, for example pines, or scrap laminated or jointed boards, to makefurniture or to construct a building, of which the durability andquality are generally poor.

Further, if the amount of wood logging is far beyond that cultivated,the environment of the Earth is affected and the global warming gasincreases to cause abnormal weather of the Earth. Further, once localforests have been consumed up, import of wood is an alternative, whichis subjected to taxation and other unfavorable conditions. For example,the raw materials may be taxed several times higher than that of thehalf-finished products. These force the manufacturers to finish theproduction in the site where the raw materials are supplied and thenexport the finished products. This is unfavorable to the manufacturersto make products in a more flexible way according to the change ofmarket.

Referring to FIG. 1 of the attached drawings, balusters must be madewith natural timber to ensure sufficient rigidity and good products ofbaluster may then be available. Due to the decreasing amount of originalforests and the shortage of timber supply, the market of wood is nowfully of wooden materials of poor quality, of which some are made bysimply jointing or combining wooden pieces to form a “composite” timber50 that is composed of multiple layers glued together. A steel material51 that is of a length of 7 cm is set in the bottom of the compositetimber 50. In a high humidity area, such as Taiwan, the composite timber50 is easily damaged. Other materials used to make balusters arereforestation wood. The reforestation wood is generally not ofsufficient rigidity and cannot be used to make good quality balusters.All these lead to a difficult of supply of wooden materials ofsufficient quality and interruption of supply often results.

It is thus desired to provide a novel structure of baluster thatovercome the above discussed problems of wooden baluster.

SUMMARY OF THE INVENTION

An object of the present invention provides a baluster structure ofhandrail, which comprises a steel-bar threaded central postcircumferentially enclosed by a plastic decorative portion and a plasticjacket, whereby the baluster is of greater strength, does not deform andbend, is safe and corrosion resistant, has an extended life span, and isenvironmentally conservative. The coarse threads of the upper and lowersections and the thread-free middle section of the steel-bar threadedcentral post are enclosed by integrally formed plastic jacket andplastic decorative portion, so that the plastic jacket and the plasticdecorative portion are rotatably fixed.

To achieve the above object, the present invention provides a balusterstructure of handrail, which comprises a steel-bar threaded centralpost, which comprises coarse threads formed on upper and lower sectionsand a thread-free middle section that are circumferentially enclosed bya plastic jacket and a plastic decorative portion. The steel-barthreaded central post has a top end forming a first joint section. Thesteel-bar threaded central post has a bottom end forming a second jointsection. The second joint section is mounted to a stairway and the firstjoint section is mounted to an underside of the handrail to form abaluster. The threads of the upper and lower sections and thethread-free middle section of the steel-bar threaded central post areenclosed by the integrally formed plastic jacket and plastic decorativeportion so as to be securely coupled to the plastic jacket and theplastic decorative portion, whereby the plastic jacket and the plasticdecorative portion are rotatably fixed. Multiple balusters are mountedto the stairway to support a handrail. The baluster is of greaterstrength, does not deform and bend, is safe and corrosion resistant, hasan extended life span, and is environmentally conservative.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be apparent to those skilled in the art byreading the following description of preferred embodiments thereof, withreference to the attached drawings, wherein:

FIG. 1 is a perspective view showing a conventional baluster made ofcomposite timber including a 7 cm steel member at the bottom thereof;

FIG. 2 is an enlarged view of a portion of a steel-bar threaded centralpost;

FIG. 3 is a perspective view showing a baluster according to anembodiment of the present invention;

FIG. 4 is a cross-sectional view of the baluster according to theembodiment of the present invention;

FIG. 5 is a schematic view showing the baluster according to theembodiment of the present invention mounted to a stairway tread and ahandrail;

FIG. 6 is a perspective view showing an application of the balusteraccording to the embodiment of the present invention to a stairwayhandrail;

FIG. 7 is a perspective view of a baluster according to anotherembodiment of the present invention;

FIG. 8 is a cross-sectional view of the baluster according to saidanother embodiment of the present invention; and

FIG. 9 is a perspective view showing an application of the balusteraccording to said another embodiment of the present invention to astairway handrail.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings and in particular to FIGS. 2-6, thepresent invention provides a baluster structure of handrail. Thebaluster structure comprises various components that will be describedas follows.

A steel-bar threaded central post 10 is formed as a one-piece uprightelongate bar. The steel-bar threaded central post 10 has a top endforming a first joint section 11. The steel-bar threaded central post 10has a bottom end forming a second joint section 12. The steel-barthreaded central post 10 has an outer circumferential surface comprisingupper and lower sections 10 b, 10 c each integrally forming a coarsethread 13 and a middle section 10 a between the upper and lower sectionsand forming no thread.

A plastic decorative portion 20 is structured to form a decorationhaving a number of (such as four) curved patterns. The coarse threads 13of the upper and lower sections 10 b, 10 c of the steel-bar threadedcentral post 10 and the thread-free middle section 10 a arecircumferentially enclosed by a shaped plastic jacket 21 that isintegrally formed with the plastic decorative portion 20 that comprisesthe four curved patterns to form a baluster 1 according to the presentinvention. The steel-bar threaded central post 10 is securely bonded tothe plastic jacket 21 and the plastic decorative portion 20 by means ofthe integrally formed plastic jacket 21 that circumferentially enclosesthe coarse threads 13 of the upper and lower sections 10 b, 10 c and thethread-free middle section 10 a and the plastic decorative portion 20,whereby the plastic jacket 21 and the plastic decorative portion 20 arenot rotatable. The second joint section 12 of the steel-bar threadedcentral post 10 is mounted to a stairway tread 30 and the first jointsection 11 if the steel-bar threaded central post 10 is mounted to anunderside 41 of a handrail 40. A plurality of balusters 1 of such astructure is mounted to the stairway to support the handrail 40 thereofthereby constructing a stairway handrail assembly 100. Further, thebaluster 1 comprises a steel-bar threaded central post 10 therein toprovide bending-resistant strength and also comprises an aestheticoutside appearance constituted by the plastic decorative portion 20.Thus, the baluster 1 has an improved strength, does not bend, is safeand corrosion resistant, has an extended life span and isenvironmentally conservative.

In the baluster structure of handrail, the first joint section 11 of thesteel-bar threaded central post 10 is mounted by a first jointingstructure 111 to the handrail 40. The first jointing structure 111comprises bonding with adhesives.

In the baluster structure of handrail, the first joint section 11 of thesteel-bar threaded central post 10 is mounted by a first jointingstructure 111 to the handrail 40. The first jointing structure 111comprises coupling with a latch pin.

In the baluster structure of handrail, the second joint section 12 ismounted by a second jointing structure 121 to the stairway tread 30. Thesecond jointing structure 121 comprises bonding with adhesives.

In the baluster structure of handrail, the second joint section 12 ismounted by a second jointing structure 121 to the stairway tread 30. Thesecond jointing structure 121 comprises bonding with concrete.

In the baluster structure of handrail, the second joint section 12 ismounted by a second jointing structure 121 to the stairway tread 30. Thesecond jointing structure 121 comprises an expansion bolt fixed in thestairway tread 30.

Referring to FIGS. 3 and 4, in the baluster structure of handrail, thesecond joint section 12 comprises a cylindrical joint section 12. Thecylindrical joint section 12 has an outer circumference on which anexposed thread 122 is formed. The exposed thread 122 allows thesteel-bar threaded central post 10 to be securely coupled without beingdriven by an external torque applied thereto to rotate.

Referring to FIG. 4, the baluster 1 comprises a steel-bar threadedcentral post 10. The steel-bar threaded central post 10 is formed as aone-piece upright elongate bar. The steel-bar threaded central post 10has a top end forming a first joint section 11. The steel-bar threadedcentral post 10 has a bottom end forming a second joint section 12. Aplastic decorative portion 20 is provided. The steel-bar threadedcentral post 10 is circumferentially enclosed by a molded plastic jacket21 that is integrally connected with the plastic decorative portion 20.

Referring to FIG. 5, the drawing shows that the first joint section 11of the steel-bar threaded central post 10 of the baluster 1 is mountedby a first jointing structure 111 to a handrail 40 and the first jointsection 11 of the steel-bar threaded central post 10 of the baluster 1is coupled by a second jointing structure 121 to a stairway tread 30.

Referring to FIGS. 7-9, the present invention provides a balusterstructure of handrail. The baluster structure comprises variouscomponents that will be described as follows.

A steel-bar threaded central post 10 is formed as a one-piece uprightelongate bar. The elongate steel-bar threaded central post 10 has anouter circumferential surface comprising upper and lower sections 10 b,10 c each integrally forming a coarse thread 13 and a middle section 10a between the upper and lower sections and forming no thread. Thesteel-bar threaded central post 10 has a top end forming a first jointsection 11. The steel-bar threaded central post 10 has a bottom endforming a second joint section 12. A plastic decorative portion 20 isstructured to form a decoration having a cylindrical shape havingcurves. The steel-bar threaded central post 10 is circumferentiallyenclosed by a shaped plastic jacket 21 that is integrally formed withthe curved cylindrical plastic decorative portion 20 to form a baluster1 according to the present invention. The steel-bar threaded centralpost 10 is securely bonded to the plastic jacket 21 and the plasticdecorative portion 20 by means of the integrally formed plastic jacket21 that circumferentially encloses the coarse threads 13 of the upperand lower sections 10 b, 10 c and the thread-free middle section 10 aand the plastic decorative portion 20, whereby the plastic jacket 21 andthe plastic decorative portion 20 are not rotatable. The second jointsection 12 of the steel-bar threaded central post 10 is mounted to astairway tread 30 and the first joint section 11 if the steel-barthreaded central post 10 is mounted to an underside 41 of a handrail 40.A plurality of balusters 1 of such a structure is mounted to thestairway to support the handrail 40 thereof thereby constructing astairway handrail assembly 100. Further, the baluster 1 comprises asteel-bar threaded central post therein to provide bending-resistantstrength and also comprises an aesthetic outside appearance constitutedby the plastic decorative portion. Thus, the baluster 1 has an improvedstrength, does not bend, is safe and corrosion resistant, has anextended life span and is environmentally conservative.

Referring to FIG. 8, the drawing shows that the steel-bar threadedcentral post 10 is circumferentially enclosed by the integrally formedplastic jacket 21 and plastic decorative portion 20. The steel-barthreaded central post 10 has a top forming a first joint section 11. Thesteel-bar threaded central post 10 has a bottom forming a second jointsection 12.

Although the present invention has been described with reference to thepreferred embodiments thereof, it is apparent to those skilled in theart that a variety of modifications and changes may be made withoutdeparting from the scope of the present invention which is intended tobe defined by the appended claims.

1. A baluster structure of a handrail, comprising: a steel-bar threadedcentral post, which is formed as a one-piece upright elongate bar, thesteel-bar threaded central post having a top end forming a first jointsection, the steel-bar threaded central post having a bottom end forminga second joint section, the steel-bar threaded central post having upperand lower sections of an outer circumferential surface each forming athread and a middle section forming no thread; and a plastic enclosureportion, the threads of the upper and lower sections and the thread-freemiddle section of the steel-bar threaded central post being completelycircumferentially enclosed by a plastic jacket that is integrally formedwith the plastic enclosure portion in such a way that the threads of theupper and lower sections of the steel-bar threaded central post areembedded in and in tight engagement with the plastic jacket to have theplastic jacket and the plastic decorative portion rotatably fixed to thesteel-bar threaded central post.
 2. The baluster structure of handrailas claimed in claim 1, wherein the first joint section of the steel-barthreaded central post is mounted by a first jointing structure to thehandrail and the first jointing structure comprises bonding withadhesives.
 3. (canceled)
 4. The baluster structure of handrail asclaimed in claim 1, wherein the second joint section is mounted by asecond jointing structure to a stairway tread and the second jointingstructure comprises bonding with adhesives.
 5. The baluster structure ofhandrail as claimed in claim 1, wherein the second joint section ismounted by a second jointing structure to a stairway tread and thesecond jointing structure comprises bonding with concrete.
 6. (canceled)7. The baluster structure of handrail as claimed in claim 1, wherein thesecond joint section comprises a cylindrical joint section, which has anouter circumference on which an exposed thread is formed.